A system in which a plurality of computers (agents) cooperate with each other to execute works along a work flow defining a process sequence has been recently introduced. For example, a technique of monitoring the capacities and load state of the agents, executing an appropriate work, and controlling the communication traffic among the agents has been known.
Related techniques are disclosed in, for example, Japanese Laid-Open Patent Publication Nos. 11-96011, and 8-123744, and Japanese National Publication of International Patent Application No. 2003-528358.